High-voltage safety switches



July 4, 1967 Rp T L 3,329,786

' HIGH-VOLTAGE SAFETY SWITCHES Filed April 27. 1964 2 Sheets-Sheet 2 a i I l S ,5 7 i Z #31 1:, s? 3 Z i 44 1/ a 'I/ 4 M 5' /7 m, 22

F INVENTORS PIERRE PICA RD JEA/VPP/fPPE MUD/AK A Rps ATTOP/VEX United States Patent 3,329,786 HIGH-VOLTAGE SAFETY SWITCHES Pierre Picard, Argenteuil, and Jean-Pierre Boudiak, Colombes, France, assignors to Societe Anonyme COQ France, a corporation of France Filed Apr. 27, 1964, Ser. No. 362,905

7 4 Claims. (Cl. 200-114) ABSTRACT OF THE DISCLOSURE A high-voltage electric safety switch for power distribution networks and the like, in which a tubular member (for each electrical phase of the system) is swingable about a horizontal pivot pin and has a pair of spacedapart internal switch contacts which can be electrically interconnected and connected by an axially movable rod within the tubular member and an actuating mechanism for this rod carried by the tubular member; the tubular member is also provided with at least one pair of external switch contacts engageable respectively with a currentinput or current-output conductor and a grounded bus bar so that, upon operation of the actuating mechanism, the internal contacts may be connected or disconnected and, upon swinging movement of the tubular member, these switch contacts can be decoupled from the network and grounded.

The present invention relates to an improved highvoltage switch or breaker device of the protected type, and to distribution stations equipped with such switches or breaker devices.

It is the essential object of this invention to provide compact switches and breaker boxes ensuring the maximum protection of the personnel likely to use them.

The switch of the present invention comprises, per electrical phase or pole, a movable tubular member or bar of insulating material having two external contacts and two internal contacts, and a sliding rod adapted to establish a connection between the two inner contacts; the improved switch is characterized in principle in that the tubular member or sleeve is adapted to oscillate about an axis and to assume at least two angular positions ensuring the connection between the input and output current leads in the first position to close the circuit and the grounding of the output current lead in the other position.

Preferably, the swingable sleeve may take between these two end positions an intermediate position corresponding to the decoupling input and output terminals of the switch.

According to a first embodiment of the safety switch of this invention the tubular member swings about a horizontal axis.

According to another embodiment, the pole swings about a vertical axis.

Other features and advantages of this invention will appear as the following description proceeds with reference to the accompanying drawing illustrating diagrammatically various forms of the invention. In the drawing:

FIG. 1 is a vertical diagrammatic section showing a cell or box of a wiring system incorporating a safety switch according to this invention;

FIG. 2 is a wiring diagram corresponding to position A (closed-load circuit) of the switch illustrated in FIG. 1;

FIG. 3 is a view similar to FIG. 1 showing a transformer cell constituting a practical application of the basic principle of the safety switch of this invention; and

FIGS. 4 and 5 are other wiring diagrams illustrating circuit arrangements corresponding to the two operative positions of the swingable tubular member of the switch according to this invention.

Before considering the subject matter of this invention,

it should be recalled that, as a rule, during the last few years the users of electrical stations for public power distribution purposes have shown a marked preference for the adoption of encloed or protected (e.g. armored) prefabricated cells or boxes; the term public power distribution designates herein transformer stations incorporating primarily medium-voltage and low-voltage transformers.

As far as high-voltage systems are concerned, these stations consist of the combination of two cell types:

(1) The so-called network cells, and (2) The so-called transformer cells.

As clearly shown in FIGS. 1 and 3 of the drawing network cells are those to which the feed cable or cables, on the one hand, and the output or distributor cable or cables, on the other hand, are connected.

The various operations to be effected, by these cells are as follows:

(a) Opening the input or output circuits under load, and closing them under load or under short-circuit conditions.

(b) Grounding and short-circuiting the output electric cable to protect the personnel on duty along the network.

(0) Interposing grounded metal shields between the bar system and the output cable in order to preserve the safety of staff members making measurements on the network at the cell concerned.

(d) Decoupling the switch from the power line to permit its maintenance.

So-called transformer cells are those designed for operating and protecting medium-voltage and low-voltage transformers. Therefore, these cells incorporate, in principle:

(a) Switch means for opening the network under load and closing the network under load or in short-circuit con- I ditions.

(b) Fuse cut-outs having a high breaking power for protecting the device against internal short-circuiting of the transformer.

(c) A device permitting the removal of the fuse elements for replacement, the operator being protected, inter alia, by the grounding and short-circuiting of the output lead to the transformer.

(d) A device for partitioning the switch (FIG. 3) for its maintenance if it is not of the decoupling type.

As will be seen from FIG. 1, the switch proper comprises a tubular member 16 (designated at its insulating sleeve) comprising as in conventional arrangements in its inner space an upper contact 3 and a lower contact 5 adapted to be interconnected by a sliding rod 4 actuated by means of a lever mechanism 15. The lower contact 5 has an external extension in the form of a strap-shaped contact 5a whose function will be explained present-1y. This tubular member 16 is mounted in a housing 1 constituting the cell or box of the device which may constitute a network cell or a transformer cell, according to its specific arrangement. This housing supports the set of bus bars 2 through which the apparatus is fed with current.

It is clear that the present invention permits a different and improved arrangement of the input and output connections, the bars 2 being disposed in the upper portion 3 and B, the former position being represented diagrammatically in FIG. 2.

Externally of the insulating tube of member 16, in the region of the upper contact 3, a double-jaw contact 3a, 3b is connected to the contact 3. These jaws are adapted to engage one of the bus bars 2 in position A and the grounding bar 12 in position B of said pole.

It is also clear that in position A the mechanism opens or closes a circuit from the input bar to the output cable through the path 2, 3a, 3, 4, 5, 22, 10a and 18. The diagram of FIG. 2 illustrates this circuit.

In position B, the mechanism opens or closes the grounding circuit of cable lead 18 without any possibility for the switch to remain energized; in this case the path is 18, 10a, 22, 5, 4, 3, 3b and 12 when the switch is closed.

If this switch is used in a transformer cel-l (FIG. 3) a fuse having high breaking power is inserted between the contact 5 and cable 18a. Contact 5 is provided with an external extension 14 formed on its free end with a jaw 14a adapted to engage, in position B as defined hereinabove, another bus bar 13 rigid with the upper contact 11 of fuse 17; the latter is plugged into a lower contact 8 electrically connected to the bar 22, on which member 16 is swingably mounted and, therefore, to contact 5. The upper contact 11 is connected directly to the head 9 of cable 18a.

The diagrams of FIGS. 4 and 5 illustrate clearly the modes of operation of the apparatus. Assuming that fuse 17 is plugged directly in its contacts 8 and 11, closure of the switch in position A will complete the circuit 2, 3, 4, 5, 22, 10a, 24, 8, 17, 11, 9 and 18a (normal operation); in position B the switch is connected in circuit 18a, 9, 11, 14a, 5, 4, 3, 13, 17, 8, 24, 10, 22, 5, 14 and 13 (FIG. 5); in other words it will ground the cable head without any possibility of accidentally energizing the device.

It will be noted that in position B even if the fuse 17 were removed from its case 7, the cable-head grounding circuit would nevertheless remain closed through the path 18a, 9, 11, 14, 5, 4, 3 and 13.

In any case the switch may be set in an intermediate position C corresponding to the draining position of the switch.

Of course, many modifications may be brought to the forms of embodiment shown and described herein without departing from the spirit and scope of the invention as set forth in the appended claims.

What we claim is:

1. A high-voltage electric safety switch enclosed in a metal housing and comprising in each phase: a current lead-in conductor and a current leado'ut conductor, a grounded bus-bar, a tubular pole of insulating material carrying an upper external contact and an upper inner contact, and a lower external contact and a lower internal contact, a conducting rod slidable along the longitudinal axis of said tubular pole, a mechanism for moving said rod from a first position to another position, said rod making an electrical connection between said internal contacts, means for electrically connecting said internal contact to the external contact of the same set, a horizontal pivot pin carried by said housing and about which said tubular pole is pivotable between two end positions, a fuse having a high breaking power, the first end of said fuse being electrically connected to one of said external contacts, the other end of said fuse being electrically connected to said current lead-out conductor, the second one of said external contacts having two sets of opposite jaws, one of said two sets of jaws ma ng c n a wi h id c rrent lead-in conductor in one of said end positions, the second one of said sets of jaws making electrical contact with the grounded bus bar in the second one of said two end positions of said tubular pole, said other end of said fuse being electrically connected to an auxiliary contact, the first one of said external contacts connected to the first end of said fuse carrying a jaw making electrical connection with said auxiliary contact in the second position of said tubular pole.

2. A high-voltage electric safety switch for at least one electrical phase, comprising:

(a) a metal housing;

(b) at least one current-input conductor, at least one current-output conductor, and at least one grounded conductor extending into said housing;

(c) a tubular member swingably mounted in said housing for swinging movement between at least two limiting positions about an axis transverse to the axis of the tubular member;

(d) a pair of axially spaced internal switch contacts within said tubular member;

(e) a conductive rod longitudinally slidable in said tubular member for electrically connecting and disconnecting said internal switch contacts upon movement of said rod in said tubular member;

(f) mechanism on said tubular member for selectively shifting said rod to electrically connect and disconnect said internal switch contacts;

(g) a pair of external switch contacts electrically connected with at least one of said internal switch contacts and mounted upon said tubular member and engageable respectively with two of said conductors in respective limiting positions of said tubular member upon the swinging movement thereof; and

(h) means for electrically connecting the other of said conductors with one of said internal contacts.

3. A switch as defined in claim 2, further comprising:

(i) a pivot pin in said housing and electrically insulated therefrom for swingably supporting said tubular member for movement between said limiting positions, the means (h) including a conductive strap forming an external contact on said tubular member engaging said pin and electrically connected with a respective one of the internal contacts (d), said pin being electrically connected with said currentoutput conductor, one of said external switch contacts (g) being engageable with said current-input conductor, the other of said external switch contacts (g) being engageable with said grounded conductor in said limiting positions, said external contacts all being constructed with jaws for positive engagement with the respective conductors and said pin.

4. A switch as defined in claim 2, further comprising:

(j) a fuse removably mounted in said housing and having one terminal electrically connectable with one of said external switch contacts and another terminal connected with said current input connector, the other of said external switch contacts having a pair of contact jaws respectively engageable with said current-output conductor and with said grounded conductor in said limiting positions of said tubular member.

No references cited.

BERNARD A. GILHEANY, Primary Examiner.

E. SPRINGBORN, Assistant Examiner, 

2. A HIGH-VOLTAGE ELECTRIC SAFETY SWITCH FOR AT LEAST ONE ELECTRICAL PHASE, COMPRISING: (A) A METAL HOUSING; (B) AT LEAST ONE CURRENT-INPUT CONDUCTOR, AT LEAST ONE CURRENT-OUTPUT CONDUCTOR, AND AT LEAST ONE GROUNDED CONDUCTOR EXTENDING INTO SAID HOUSING; (C) A TUBULAR MEMBER SWINGABLY MOUNTED IN SAID HOUSING FOR SWINGING MOVEMENT BETWEEN AT LEAST TWO LIMITING POSITIONS ABOUT AN AXIS TRANSVERSE TO THE AXIS OF THE TUBULAR MEMBER; (B) A PAIR OF AXIALLY SPACED INTERNAL SWITCH CONTACTS WITHIN SAID TUBULAR MEMBER; (E) A CONDUCTIVE ROD LONGITUDINALLY SLIDABLE IN SAID TUBULAR MEMBER FOR ELECTRICALLY CONNECTING AND DISCONNECTING SAID INTERNAL SWITCH CONTACTS UPON MOVEMENT OF SAID ROD IN SAID TUBULAR MEMBER; (F) MECHANISM ON SAID TUBULAR MEMBER FOR SELECTIVELY SHIFTING SAID ROD TO ELECTRICALLY CONNECT AND DISCONNECT SAID INTERNAL SWITCH CONTACTS; (G) A PAIR OF EXTERNAL SWITCH CONTACTS ELECTRICALLY CONNECTED WITH AT LEAST ONE OF SAID INTERNAL SWITCH CONTACTS AND MOUNTED UPON SAID TUBULAR MEMBER AND ENGAGEABLE RESPECTIVELY WITH TWO OF SAID CONDUCTORS IN RESPECTIVE LIMITING POSITIONS OF SAID TUBULAR MEMBER UPON THE SWINGING MOVEMENT THEREOF; AND (H) MEANS FOR ELECTRICALLY CONNECTING THE OTHER OF SAID CONDUCTORS WITH ONE OF SAID INTERNAL CONTACTS. 